Swathi Ravipudi et al /J. Pharm. Sci. & Res. Vol. 9(2), 2017, 215-220

Gingival Recession: Short Literature Review on Etiology, Classifications and Various Treatment Options.

Swathi Ravipudi , Devapriya Appukuttan, P.S.G. Prakash, D.J. Victor Savitha Dental College and Hospitals, Chennai

Abstract Gingival recession is the term that designates the oral exposure of the root surface due to a displacement of the apical to the cement-enamel junction. It is the most common and undesirable condition of the gingiva. The etiology is multifactorial and includes excessive or inadequate teeth brushing, destructive , malposition, alveolar bone dehiscence, high muscle attachment, aberrant frenal pull, , iatrogenic factors and smoking. It is ideally recommended to have an adequate mucogingival complex so that the MG tissues can sustain their bio-morphological integrity and maintain an enduring attachment to the teeth and the underlying soft tissues. Complete information on marginal tissue recession is essential for diagnosis, prognosis, treatment planning, and for communication between clinicians. However, most of the classifications are unable to convey all the relevant information related to marginal tissue recession. Hence, this review broadly discusses the possible causative factors, classifications including the various treatment options for GR. Keywords: Gingival Recession, classification, treatment options.

INTRODUCTION: Gingival recession (GR) is the term that designates the oral Local factors: Plaque and have been associated exposure of the root surface due to a displacement of the with inflammation in the connective tissue (CT) adjacent to gingival margin apical to the cement-enamel junction the resulting in development of (CEJ).[1,2] It is the most common and undesirable condition GR.[8,9] of the gingiva and its prevalence commonly increases with age.[3,4] GR either localized or generalized, is one of the Periodontal disease: The interaction between bacteria clinical features of periodontal disease and is frequently present in the plaque and immune response of the host associated with clinical problems such as root surface results in matrix degradation, bone resorption, and down- hypersensitivity, root caries, cervical root abrasions, growth of the epithelium, resulting in periodontal pockets, erosions, plaque retention and aesthetic dis-satisfaction.[5,6] GR, or a combination of both.[10] The etiology is multifactorial and includes excessive or inadequate teeth brushing, destructive periodontal disease, Mechanical forces: Faulty is a common tooth malposition, alveolar bone dehiscence, high muscle cause of GR. Aggressive tooth brushing gradually abrades attachment, aberrant frenal pull, occlusal trauma, iatrogenic the gingival tissue. The gingiva appears free of factors (such as orthodontic, or prosthetic treatment) and inflammation however the apical shift of the marginal smoking.[7] gingiva exposes the root surfaces.[11-13]Friction from the It is ideally recommended to have an adequate soft tissues i.e. gingival ablation has been implicated in GR. mucogingival (MG)complex so that the MG tissues can Occlusal traumatism is also an etiologic factor leading to sustain their bio-morphological integrity and maintain an MG problems[14,15] but its mechanism of action has never enduring attachment to the teeth and the underlying soft been demonstrated. tissues. The MG problems can present either as close disruption resulting in pocket formation or as open Iatrogenic factors: Orthodontic tooth movement can alter disruption resulting in gingival clefts and GR.[5] the marginal and the papillary tissue. Creation of Complete information on marginal tissue recession is dehiscence during orthodontic movement often results in essential for diagnosis, prognosis, treatment planning, and GR, more commonly this occurs in the lower incisors and for communication between clinicians. However, most of the mesio-buccal root of first molars, especially in premolar the classifications are unable to convey all the relevant extraction cases, but it can occur in any location. Studies information related to marginal tissue recession. Hence, have shown that the volume of soft tissue may be a key this review broadly discusses the possible causative factors, factor in predicting whether GR will occur during or after classifications including the various treatment options for orthodontic therapy. GR. Restorative and prosthodontic procedures like preparations extending subgingivally, impression Etiology of GR techniques involving gingival retraction, sub-gingivally The common etiologic factors are (1) local factors, (2) placed restorations and crowns and overhanging periodontal disease, (3) mechanical forces, (4) iatrogenic restorations.[16]Similarly, poorly designed dentures and factors, and (5) anatomical factors.

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clasp placements can favor plaque accumulation around the CLASSIFICATION OF GR: abutment teeth consequently to GR.[17,18] Classifications are used both as diagnostic and prognostic tools for root coverage procedures. Anatomical factors: Alveolar bone dehiscence, aberrant Sullivan and Atkins in 1968[30]classified GR into four frenal attachment, tooth position and gingival morphology categories according to their morphology as Deep and can play role in GR development.[19-25] Narrow band of Wide, Shallow and Wide, Deep and Narrow, Shallow and keratinized gingiva(KG) is commonly associated with Narrow. [Figure 1] GR.[19,20] However, some studies refute the idea and have Bengue et al in 1983[31] classified the recessions based on shown that with appropriate periodontal maintenance, areas their morphology and prognosis: "U" type recession has of inadequate KG do not demonstrate further GR when poor prognosis, "V" type recession has fair prognosis and compared with grafted gingival sites. Nevertheless, in "I" type recession has good prognosis.[Figure 2] patients who discontinued the maintenance program, Miller in 1985[32] proposed a classification which is the inflammation recurred concomitant with recession.[26] most widely used today. Miller's classification is as The morphology or biotype of the can be thin follows: Class I—Marginal tissue recession that does not and scalloped, or thick and flat. [27] Recession of the extend to the (MGJ), with no papillary and facial gingiva is common in thin biotype periodontal loss in the interdental area; the tooth is well because the bone is also thin and there is higher incidence aligned in the arch. One hundred percent root coverage can of dehiscence and fenestrations in thin bone. Minimal be anticipated. Class II—Marginal tissue recession that brushing force can result in soft tissue recession and extends to or beyond the MGJ, with no periodontal loss in exposure of the root in teeth with dehiscence covered with the interdental area; the tooth is well-aligned in the arch. thin gingiva. Recession often continues until the soft tissue One hundred percent root coverage can be anticipated. margin approaches the bone margin however, it fails to Class III—Marginal tissue recession that extends to or proceed in the absence of inflammation and this beyond the MGJ; bone or soft tissue loss in the interdental phenomenon has been termed as self-limiting recession. area is present, or there is mal-positioning of the teeth. The position of the tooth in relation to the bucco-lingual Partial root coverage can be expected. Class IV—Marginal dimension of the has an effect on the tissue recession that extends to or beyond the MGJ. The position and thickness of the gingiva that will be bone or soft tissue loss in the interdental area and/or mal- established around the teeth. When a tooth is positioned positioning of the teeth is so severe that root coverage facially, the bone and soft tissue on the facial of that tooth should not be attempted. are thinner and more susceptible to soft tissue recession Mahajan modification of Miller’s classification[33] in than the adjacent teeth. Studies have also shown association 2010,Mahajan classified GR based on the severity of soft between root prominence and GR. and hard tissue loss in the inter-proximal area. Class I:GRD not extending to the MGJ, Class II: GRD extending to the PATHOGENESIS OF GINGIVAL RECESSION MGJ/beyond it, Class III: GRD with bone or soft-tissue The mechanism of GR due to localized inflammatory loss in the interdental area up to cervical 1/3 of the root processes in CT with the accumulation of mononuclear surface and/or mal-positioning of the teeth and Class IV: cells was described by Baker and Seymour in 1976[28] GRD with severe bone or soft tissue loss in the interdental they explained the different stages in the development of area greater than cervical 1/3rd of the root surface and/or GR. In the initial stage there is normal or subclinical severe mal-positioning of the teeth. Based on the class of inflammation, following this inflammation appears recession prognosis was suggested. Class I and Class II clinically and histologically there is proliferation of with thick gingival profile has best prognosis, Class I and epithelial rete pegs. Stage 3 shows increased epithelial Class II with thin gingival profile has good prognosis, Class proliferation resulting in loss of CT core and finally there is III with thick gingival profile has fair prognosis and Class merging of oral and resulting in III and Class IV with thin gingival profile has poor separation and recession of the gingival tissues due to loss prognosis. of nutritional supply. Smith’s index of recession (IR) 1997[34]in this index two Waerhaug[29] proposed that the distance between the digits separated by a hyphen describe the horizontal and periphery of plaque on the tooth surface and the labial, vertical components of a recession site, prefixed by F or L. apical extension of the inflammatory infiltrate hardly ever The horizontal component is a whole number value exceeds 1-2 mm. Thus if the free gingiva is voluminous the between 0–5depending on the severity of the CEJ exposure infiltrate will occupy only a small portion of the connective on either the facial or lingual aspects of the tooth, between tissue however, if it is thin the entire connective tissue the mesial and distal midpoints .The second digit of the IR portion may be involved consequently there is proliferation gives the vertical extent of recession measured in of epithelial cells from the oral and dento-gingival millimeters on a range from 0–9. An asterisk denotes epithelium. Thus the zone of CT decreases and it is involvement of the MGJ. Table 1 and 2 shows the scoring obliterated by the fusion of these two epithelia. Finally, the based on the extent of recession. epithelium loses its nutritional source, and GR ensues.

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Figure 1: Sullivan & Atkins Classification

Figure 2: Bengue classification

Figure 3: Nordland & Tarnow’s classification

1- The interdental contact point

2- The apical extent of the facial CEJ 3- The coronal extent of the proximal CEJ

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Table 1: Shows the scoring for horizontal extent of recession in Smith’s index for GR The horizontal extent of recession Score Criteria O No clinical evidence of root exposure No clinical evidence of root exposure plus a subjective awareness of dentinal hypersensitivity in response 1 to a 1 sec air blast, and/or there is clinically detectable exposure of the CEJ for upto 10% of the estimated midmesial to mid distal distance 2 Horizontal exposure of the CEJ > 10% but < 25% of the estimated midmesial to mid distal distance. 3 Exposure of the CEJ >25%of the mid mesial to mid distal distance but not exceeding 50% 4 Exposure of the CEJ >50%of the mid mesial to mid distal distance but not exceeding 75% 5 Exposure of the CEJ >75%of the mid mesial to mid distal distance upto 100%

Table 2: Shows the scoring for vertical extent of recession in Smith’s index for GR The vertical extent of recession Score Criteria O No clinical evidence of root exposure No clinical root exposure plus a subjective awareness of dentinal hypersensitivity is reported and/or there is 1 clinically detectable exposure of the CEJ not exceeding > 1mm vertical to the gingival margin. 2 to 8 Root exposure 2 to 8 mm extending vertically from the CEJ to the base of the soft tissue defect 9 Root exposure > 8mm from the CEJ to the base of the soft tissue defect.

Nordland and Tarnow 1998[35] proposed a classification recession on F/L aspect. Class II-B: Gingival margin on system for interproximal papillary height based on three F/L aspect lies apical to CEJ but coronal to MGJ with anatomical landmarks: The interdental contact point, the attached gingiva present between marginal gingiva and apical extent of the facial CEJ and the coronal extent of the MGJ. Class II-C: Gingival margin on F/L aspect lies at or proximal CEJ. Normal: fills embrasure apical to MGJ with an absence of attached gingiva between space to the apical extent of the interdental contact marginal gingiva and MGJ. Either of the subdivisions can point/area. Class I: tip of interdental papilla lies between be on F or L aspect or both (F and L). the interdental contact point and most coronal extent of Class III: The tip of the interdental papilla is located at or interdental CEJ. Class II: tip of interdental papilla lies apical to the level of the CEJ mid-buccally/lingually. apical to interproximal CEJ but coronal to apical extent of Interproximal bone loss is visible on the radiograph. This is facial CEJ. Class III: tip of interdental papilla lies in level sub classified into 2 categories: Class III-A: Gingival with or apical to facial CEJ. Figure 3 shows the margin on F/L aspect lies apical to CEJ, but coronal to classification. MGJ with attached gingiva present. Class III-B: Gingival Cairo classification in 2011[36] proposed a newer margin on F/L aspect lies at o apical to MGJ with an classification using the inter-dental clinical attachment absence of attached gingiva between marginal gingiva and level (ICAL) as an identification criterion wherein MGJ. Either of the subdivisions can be on F or L aspect or Recession Type 1 (RT1) is associated with no interdental both(F and L). attachment loss, Recession Type 2 (RT2) the loss of ICAL Classification of palatal GR: The position of interdental is equal or smaller than the buccal attachment loss and papilla remains the basis of classifying gingival recession Recession Type 3 (RT3) the loss of ICAL is higher than the on palatal aspect. The criteria of sub-classifications have amount of buccal attachment loss. been modified to compensate for the absence of MGJ. Ashish Kumar in 2013[37] classified recessions on the Palatal recession-1: There is no loss of interdental bone or facial surfaces of maxillary teeth, palatal recessions, facial soft-tissue. This is sub divided into two categories. PR-1-A: and lingual recessions of mandibular teeth, including marginal tissue recession ≤3mm from CEJ. PR-I-B: interdental papillary recessions. Marginal tissue recession of >3mm from CEJ. Class I: there is no loss of interdental bone or soft tissue. Palatal recession II: The tip of the interdental papilla is This is sub classified into 2 groups: Class I-A: Gingival located between the interdental contact point and the level margin on F/L aspect lies apical to CEJ, but coronal to of the CEJ mid-palatally. Interproximal bone loss is visible MGJ with attached gingiva present between marginal on the radiograph. This is sub divided into two categories. gingiva and MGJ.Class I-B: Gingival margin on F/L aspect PR-II-AS: Marginal tissue recession ≤3mm from CEJ. PR- lies at or apical to MGJ with an absence of attached gingiva II-B: Marginal tissue recession of >3mm from CEJ between marginal gingiva and MGJ. Either of the Palatal recession III: The tip of the interdental papilla is subdivisions can be on F or L aspect or both(F and L). located at or apical to the level of the CEJ mid-palatally. Class II: The tip of the interdental papilla is located Interproximal bone loss is visible on the radiograph.PR-III- between the interdental contact point and the level at the A: Marginal tissue recession of ≤3mm from CEJ. PR-III-B: CEJ mid-buccally/mid-lingually. Interproximal bone loss is Marginal tissue recession of >3mm from CEJ visible on the radiograph. This is sub classified into 3 categories. Class II-A: There is no marginal tissue TREATMENT OPTIONS:

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NON-SURGICAL TREATMENT OPTIONS: (Connective tissue graft (CTG) along with CAF/ Laterally The objectives of nonsurgical therapy are to maintain or positioned flap/ Double papilla flap/ Envelope technique, or improve the periodontium and the exposed root surfaces a (FGG) with CAF). when the findings and diagnosis do not warrant surgical If deep periodontal pockets with a probing depth >5mm is treatment or when contraindications to surgery exist. evident, and KT is adequate then GTR technique can be If the recession defect is minimal, not in the aesthetic area carried out along with CAF. Inadequate amount of KT with no associated dentine hypersensitivity or root caries no apical to the recession indicates the need for free soft tissue treatment is indicated. It is imperative to identify and graft along with a membrane and CAF. manage the etiology inorder to prevent further recession. According to Craiz Galanza, when there is presence of Additionally, it is also important to maintain good oral adequate width of attached gingiva (WAG) perceived hygiene so that plaque induced gingival inflammation is esthetic needs with no or removable root caries, a coronally prevented as it can result in further recession especially in positioned graft is advisable. When the WAG is inadequate thin gingival biotypes. In specific cases where the patient with perceived esthetic needs and adequate donor tissue is has a high smile line and the gingival zeniths are uneven available, a CTG/FGG is recommended. A two stage due to recession or where root caries or dentine surgical procedure wherein stage I Pedicle graft is hypersensitivity develops it may be necessary for recommended followed by stage II maintenance) is advised intervention and management. If the patient’s primarily in the presence of root caries. complains of sensitivity and aesthetics is not of much concern, then management of sensitivity using CONCLUSION: commercially available desensitizing agents alone may be Management of recession and its sequelae is based on a sufficient.[38]Small localized recession defects with thorough assessment of the etiological factors and the sensitivity, wear or caries of the root surface can be degree of involvement of the tissues. It goes without corrected by bonding tooth colored composite over the saying, that therapeutic interventions will be undermined in exposed root surface. Careful placement of the composite the long run if the cause of the problem is not removed. restoration is essential to ensure that there are no plaque Once the etiology of the condition has been uncovered and retentive margins which would promote further gingival addressed, a treatment plan to arrest or reverse the gingival recession.[39] recession should be formulated. The initial part of the Recession along with loss of interdental papillae results in management of the patient with gingival recession should spacing between the teeth these are referred to as ‘black be preventive and the degree of gingival recession should triangles’. Some patients also complain of altered speech be monitored for further signs of progression. Given the due to air escaping through these spaces inter-proximally. focus on conservative therapy in modern dentistry, The use of a removable gingival prosthesis can replace preventive therapy in the form of proper dietary and oral large volumes of receded soft tissue, fill the interproximal hygiene instruction should be the first line of defense spaces to eliminate the black triangles and improve against gingival recession. Prevention can be supplemented aesthetics.[38] with scaling, polishing and root planing at appropriate Mal-positioned teeth either buccally/ labially may have a intervals based on patient risk factors. Due to their invasive buccal dehiscence or associated recession. This is most nature, surgeries are a last source of treatment, and should often seen in buccally placed lower incisors where there is be used in patients who present with severe recession crowding of the lower labial segment. If the patient is and/or extensive sensitivity and esthetic concerns. 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